Water-tube boiler



(No Model.) 2 Sheet--Sheet 1.

S..A.`PRATT WATER TUBE BOILER- No. 495,682. Patented Apr. 18,1893.

l n l I W JW v 0% n c fl f M M Q/ f NYI Sw. V fw l/ S /l l m o m m VIU.9. l m o H N2 Hrm.

.Q al F r |l.wh. 1 V [11| 5 z /M .o MN wvl. F-l. .E boo oo\\m ooooooo.m\ o WW 9M. t nu e .n s s t .e e h s 2 um Tw mlm AB RE Pw. .T AR .n .SAW .u d4 o M o m.

Patented A Yw OO. l0. 069Go o M JW. Q@ @E @E o OOO @ko o boiler head,that command the ends of the- Nrrnn STATES PATENT Trice.

STEPHEN A. PRATT, OF DETROIT, MICHIGAN.

WATER-TUBE BOILER.

SPECIFICATION forming part of Letters Patent No. 495,682, dated April18, 1893. I Application filed May 1l, 1892. Serial No.4321598. (Nomodel.)

To a/ZZ whom it may concern:

Be it known that I, STEPHEN A. PRATT, a citizen of the United States,residing at Detroit, in the county of Wayne and State of Michigan, haveinvented certain new and useful Improvements in Water-Tube Boilers;

and I do declare the following to be a full, clear, and exactdescription of theinvention, such as will enable others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawings, and to the letters of reference markedthereon, which form apartof this specilication.

This invention relates to new and useful improvements in water tubeboilers, and consists in a certain construction and arrangement ofparts, as hereinafter fully set forth, the essential features of whichbeing pointed out particularly in the claims.

The object of the invention is to produce a water-tube boiler, in whichstrength and durability are effected as well as economy in construction,and in which the water-'tubes are made readily accessible for thepurpose of cleaning or repair, and a perfect circulation of the watermaintained within the boiler. This object is attained by theconstruction illustrated in the accompanying drawings, in which Figure lis a Vertical longitudinal section through the boiler and inclosingbrick-work, the boiler being sectioned as on dotted line l-l of Fig. 2.Fig. 2 is a front elevation ofI the boiler, showing some of the capsremoved from the apertures in the outer plate of the tubes, and alsoshowing a portion of said plate broken away. Fig. 3 is an enlargedhorizontal section through the boiler as taken on dotted lines 3-3 ofFig. 2. Fig. 4 is an enlarged vertical section through the steam- `drumand its connection with the water-front of the boiler.

Referring to the letters of reference, A indicates the tubes of theboiler, which are arranged alternately, and whose ends are expanded, atthe front and rear,iu the plates B and C respectively which form theinner shells of the water space at the ends of the'l5o boiler.

Located adjacent to the plates B, C but separated therefrom by thedividing rings D,

`D', are the respective plates E, F, said plates being secured to saidrings by means of the bolts or rivets d passing therethrough, as clearlyshown in Figs. l and 3, and yare provided with a series of triangularapertures b located directly opposite and commanding the ends of thewater tubes A, in series of three, clearly shown in Fig. 2, saidapertures being covered with the triangular caps f secured in place bythe stay bolts el that are anchored in the inner plate B, C and whichpass through said caps and receive the nuts c. These bolts d not onlyserve to secure the capsf, but assist in staying the plates B, C whichare additionally stayed by the interposed bolts e crossing transverselybetween said plates. This formation and arrangement of parts produces awater space at both ends of the tubes A with which all of said tubescommunicate, and renders either end of said tubes readily accessible bythe removal of the cap from the opposed aperture in the outer plates.

H designates a steam-drum, which is located above the tubes of theboiler and coinmunicates therewith through the water-front andwater-bacl, the communication at the front being effected through thehollow cast coupling I, which is concaved at its upper end to receivethe steam-drum H which lies therein, said coupling having the extendingiiange t' through which it is riveted to the shell of said drum, whoselower arc is provided with an oblong aperture h, as shown in Fig. '4.,that opens into the hollow of the coupling. The base J of said couplingrests upon the ring D apertured to receive the nipples m which passtherethrough and through said ring, as also shown in Fig. 4, wherebycommunication is established' between the steam-drum and the water-frontof the boiler.

The rear connection between the steamdrum and the water-back isaccomplished in the same manner through the employment of a likecoupling I which communicates with the water-back through the tube ortubes K,

as shown in Fig. l, by which means a perfect and unimpeded circulationis effected through the Water tubes and the steam-drum of the boiler,which as Will be understood are filled with Water, the normal Water linebeing at the horizontal diameter of the steam drum, as shown by dottedline G in Fig. 4.

L indicates the mud-drum which is located below the water-back andconnected directly therewith.

While I have shown and described the re movable caps f as. triangular inform and as covering or commanding the ends of the Water tubes in seriesof three; it is evident that the number and location of the tubes in theboiler will determine the size and shape of said caps. They may be madeto command four or more tubes or even less than three, if desired. Asshown in Fig. 1, the boiler tubes are located obliquely within suitablebrick- Work, above which the steam-drum is supported in a horizontalposition.

Having thus fully set forth my invention, what I claim as new, anddesire to secure by Letters Patent, is-

1. In a boiler the combination of the tubes, the adjacent plates forminga Water space with which said tubes communicate, the outer plate havinga series of angular apertures therein each of said apertures beingopposite and commanding the ends of a plurality of said tubes, theangular caps adapted to independently close each of said apertures, and

being removably secured in place the stay bolts secured in the innerplate and passing through said caps, substantially as specified.

2. In a boiler, the combination of the tubes, the outer and inner endplates, the interposed ring to which said plates are secured forming awater space with which said tubes communicate, the outer plate having aseries of apertures therein each of said apertures being opposite theends ot' a plurality of said tubes, the removable caps covering saidapertures, the transverse stay bolts anchored in the inner plate andpassing through said caps to retain them in place, substantiallyasspecified.

3. In a boiler, the combination of the alternating tubes, the adjacentplates and interposed ring forming a .water-space with which said tubescommunicate, the outer plate having a series of angular aperturestherein arranged opposite and commanding the ends of a plurality of saidtubes, the angular caps adapted to close said apertures,and thestaybolts passing through the inner plate and through said caps, wherebythe caps are retained in place over said apertures, and said plates arestayed, substantially as specified.

In testimony whereof I affix my signature in presence of two Witnesses.

STEPHEN A. PRATT. Witnesses:

E. S. WHEELER, I-I. R. WHEELER.

ssv

